I'm getting s a wirring noise from my 300CE (M103)..it sounds like an electric pump under the bonnet! Its intermittant..sort of.. 'Whhr... WRRRRRRRRR. Whr Whr' etc. I havent been able to locate the source of the noise since its always dark outside when i travel !
It only happens on a hot engine at idle in park or nuetral. If I put the car to Drive or Reverse, the noise stops. ?? Could it be the tranny pump? Shifts are fine.
As for the oil pressure, on a cold engine (5degC) The pressure needle sits at 0 for 3 seconds, then takes 2 seconds to reach 3 where it stays. Once the engine has been run for about 20 seconds, and switched off for 5 mins... the oild pressure goes immediately up to 3. Is this normal?
Bri <worried his oil pump is about to go pop>